package com.zhang.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.sun.prism.impl.BaseContext;
import com.zhang.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.Objects;

/**
 * 实现明天理想的唯一障碍是今天的疑虑
 *
 * @Author {张旭军}
 * @Date: 2023/02/03/ 11:00
 * @description
 */


@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {

    /**
     * 路径匹配器，支持通配符
     */
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();


    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1、获取本次请求的URI
        String requestUri = request.getRequestURI();

        log.info("拦截到请求：{}",requestUri);

        //定义不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**"
        };

        //2、判断本次请求是否需要处理
        boolean check = check(urls, requestUri);

        //3、如果不需要处理，则直接放行
        if(check){
            log.info("本次请求{}不需要处理",requestUri);
            filterChain.doFilter(request,response);
            return;
        }

        //4-1、判断登录状态，如果已登录，则直接放行
        Object employee = request.getSession().getAttribute("employee");
        if(employee != null){
            log.info("用户已登录，用户id为：{}",request.getSession().getAttribute("employee"));

            Long empId = (Long) request.getSession().getAttribute("employee");

            filterChain.doFilter(request,response);
            return;
        }

        //4-2、判断登录状态，如果已登录，则直接放行
        if(request.getSession().getAttribute("user") != null){
            log.info("用户已登录，用户id为：{}",request.getSession().getAttribute("user"));

            Long userId = (Long) request.getSession().getAttribute("user");

            filterChain.doFilter(request,response);
            return;
        }

        log.info("用户未登录");
        //5、如果未登录则返回未登录结果，通过输出流方式向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
    }

    /**
     * 路径匹配，检查本次请求是否需要放行
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls,String requestURI){
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if(match){
                return true;
            }
        }
        return false;
    }
}
